My brother told me that in one TF2 match he was playing Pyro, and another Pyro came by... with the same username as him. Because of that giveaway, the Pyro-disguised Spy ended up with the same fate as this one.

A similar thing happened to me too- I was wandering around on one of the control point maps (completely lost xD ) and just as I rounded a corner I happened to see another red Pyro appear out of thin air. Poor spy.